Drawing a pixel is all well and good...but if it were a pixel in an FSX aircraft's skin it'd need to be in DXT5 compression [which is inverted], have an alpha channel for shine, an accompanying specular mapping [also in DXT5 with alpha]....and of course a bump-map image......now THAT one is going to be difficult as it needs a few-pixel offset to generate the 'bump'.
All up that's going to be 6 images....
Now, if you want to see it at night you'll also need one more image [pair] showing the emissive mapping of the....er....pixel.
Sometimes I really think WB skinning is just too easy....